NDT Thickness Measurements for Concrete Pavements - It ......Other states evaluating the technology...
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MAGNETIC PULSE INDUCTION TECHNOLOGY MIT SCAN T2 (SCAN T2) is a commercially available device that uses Magnetic Pulse Induction technology to determine thickness of concrete pavement in a nondestructive manner. It provides the same level of accuracy and can save time and money for state agencies when compared to coring the pavement for thickness determination. PAVEMENT THICKNESS Life of pavement is significantly influenced by Pavement Thickness. Pavement Thickness measurement is an important QA activity for agencies. CURRENT METHODS TO MEASURE PAVEMENT THICKNESS Probing (Quality Control). Coring (Most Prevalent) (Acceptance). - AASHTO T148 / ASTM C 174 - Typical Frequency - One Core per 2000 sq.yds of pavement. Other non destructive methods - Impact Echo. - Ground Penetrating Radar (GPR). CORING - LIMITATIONS Destructive. Expensive. Time Consuming ( Activities Include: Coring, inspecting, handling, measuring core lengths, patching core holes). IMPLEMENTATION ACTIVITIES Scan T2 Domestic Target Studies: - Concrete Pavement Technology Program (CPTP). - Iowa DOT. Targets made of locally available sheet metals are able to produce consistent measurements. ASTM A653, CS Type B, G90 galvanized sheet metal. Iowa DOT NDT Thickness Specification. (http://www.iowadot.gov/specifications/dev_specs/DS-09063.pdf ) ADVANTAGES of Scan T2 VS. OTHER METHODS Accuracy within 0.08”. Easy to use. Rapid Measurement. Cost savings of three to five times compared to coring. Non-Destructive. Independent of the base material. Independent of the Maturity of the concrete. Ability to measure pavement thickness a second time after grinding is performed. LIMITATIONS Scan T2 targets cannot be placed within 2 ft of other metal. Scan T2 cannot be used on CRC or JRC Pavements. CONCLUSIONS Magnetic Pulse Induction offers a faster, cheaper, accurate and non-destructive way to measure pavement thickness. It offers many advantages compared to other non-destructive technologies to measure pavement thickness. Iowa DOT has successfully implemented this technology in their specifications for measuring pavement thickness. ONGOING EFFORTS Identify US Source of Targets. Other states evaluating the technology to potentially include it in their specifications. Development of AASHTO Standard Test Method. Demonstration via FHWA’s Mobile Concrete Laboratory (MCL). Equipment Loan via FHWA’s Advanced Concrete Pavement Technology (ACPT) Program. NDT Thickness Measurements for Concrete Pavements - It really works! Jim Grove, Kevin Jones, Dan Ye, and Jagan Gudimettla TRB Paper 12-2081 OPERATION OF THE SCAN T2 ACCURACY REPEATABILITY Target Placement Target Nailed to the Base Scanning Operation Target Locating Thickness Measurement FIELD PERFORMANCE Cores over Dense Graded versus Open Graded Bases ORIENTATION OF SQUARE TARGETS 9 point - Core Length Measurement SCAN T2 VS. CORES TWO SCAN T2 DEVICES AT SAME LOCATIONS TARGET STUDY Diameter : 12inches
Transcript of NDT Thickness Measurements for Concrete Pavements - It ......Other states evaluating the technology...
MAGNETIC PULSE INDUCTION TECHNOLOGY
MIT SCAN T2 (SCAN T2) is a commercially available device that uses Magnetic Pulse Induction technology to determine thickness of concrete pavement in a nondestructive manner. It provides the same level of accuracy and can save time and money for state agencies when compared to coring the pavement for thickness determination.
PAVEMENT THICKNESS
Life of pavement is significantly influenced by Pavement Thickness. Pavement Thickness measurement is an important QA activity for agencies.
CURRENT METHODS TO MEASURE PAVEMENT THICKNESS
Probing (Quality Control). Coring (Most Prevalent) (Acceptance).
- AASHTO T148 / ASTM C 174 - Typical Frequency - One Core per 2000 sq.yds of pavement.
Other non destructive methods
- Impact Echo. - Ground Penetrating Radar (GPR).
CORING - LIMITATIONS
Destructive. Expensive. Time Consuming ( Activities Include: Coring, inspecting, handling, measuring core lengths, patching core holes).
IMPLEMENTATION ACTIVITIES
Scan T2 Domestic Target Studies: - Concrete Pavement Technology Program (CPTP). - Iowa DOT.
Targets made of locally available sheet metals are able to produce consistent measurements. ASTM A653, CS Type B, G90 galvanized sheet metal. Iowa DOT NDT Thickness Specification.
(http://www.iowadot.gov/specifications/dev_specs/DS-09063.pdf)
ADVANTAGES of Scan T2 VS. OTHER METHODS Accuracy within 0.08”. Easy to use. Rapid Measurement. Cost savings of three to five times compared to coring. Non-Destructive. Independent of the base material. Independent of the Maturity of the concrete. Ability to measure pavement thickness a second time after grinding is performed.
LIMITATIONS
Scan T2 targets cannot be placed within 2 ft of other metal. Scan T2 cannot be used on CRC or JRC Pavements.
CONCLUSIONS
Magnetic Pulse Induction offers a faster, cheaper, accurate and non-destructive way to measure pavement thickness. It offers many advantages compared to other non-destructive technologies to measure pavement thickness. Iowa DOT has successfully implemented this technology in their specifications for measuring pavement thickness.
ONGOING EFFORTS
Identify US Source of Targets. Other states evaluating the technology to potentially include it in their specifications. Development of AASHTO Standard Test Method. Demonstration via FHWA’s Mobile Concrete Laboratory (MCL). Equipment Loan via FHWA’s Advanced Concrete Pavement Technology (ACPT) Program.
NDT Thickness Measurements for Concrete Pavements - It really works! Jim Grove, Kevin Jones, Dan Ye, and Jagan Gudimettla
TRB Paper 12-2081
OPERATION OF THE SCAN T2
ACCURACY REPEATABILITY
Target Placement Target Nailed to the Base Scanning Operation Target Locating Thickness Measurement
FIELD PERFORMANCE
Cores over Dense Graded versus Open Graded Bases
ORIENTATION OF SQUARE TARGETS
9 point - Core Length Measurement
SCAN T2 VS. CORES TWO SCAN T2 DEVICES AT SAME LOCATIONS
TARGET STUDY
Diameter : 12inches
